A retractile testicle is a testicle that may move back and forth between the scrotum and the groin. When the retractile testicle is residing in the groin, it may be easily guided by hand into its proper position in the scrotum — the bag of skin hanging behind the penis — during a physical examination.

For most boys, the problem of a retractile testicle goes away sometime before or during puberty, the time when an out-of-place testicle moves to its correct location in the scrotum and stays there permanently.

About a quarter of the time, the retractile testicle stays up in the groin and is no longer movable. When this happens, the condition is called an ascending testicle.

Testicles form in the abdomen during fetal development. During the final months of development, the testicles gradually descend into the scrotum. If your son has a retractile testicle, the testicle originally descended as it should, but then it didn't remain in place.

Signs and symptoms of a retractile testicle include the following:

The testicle may be moved by hand from the groin into the scrotum and won't immediately retreat to the groin.

It may spontaneously appear in the scrotum and remain there for a time.

It may spontaneously disappear again for a time.

The movement of the testicle almost always occurs without pain or discomfort. Therefore, a retractile testicle is noticed only when it is no longer seen or felt in the scrotum.

The position of one testicle is usually independent of the position of the other one. For example, a boy may have one normal testicle and one retractile testicle.

Retractile testicle is different from undescended testicle (cryptorchidism). The undescended testicle is one that never entered the scrotum. If a doctor attempted to guide an undescended testicle, it would cause discomfort or pain.

When to see a doctor

During regular well-baby checkups and annual childhood checkups, your son's doctor examines your son's testicles to determine if they're descended and appropriately developed. If you believe that your son has a retractile or ascending testicle — or have other concerns about the development of his testicles — see his doctor. He or she will tell you how often to schedule checkups to monitor changes in the condition.

If your son experiences pain in the groin or testicles, see your son's doctor immediately.

An overactive muscle causes a testicle to become a retractile testicle. The cremaster muscle is a thin pouch-like muscle in which a testicle rests. When the cremaster muscle contracts, it pulls the testicle up toward the body.

The main purpose of the cremaster muscle is to control the temperature of the testicle. In order for a testicle to develop and function properly, it needs to be slightly cooler than normal body temperature. When the environment is warm, the cremaster muscle is relaxed; when the environment is cold, the muscle contracts and draws the testicle toward the warmth of the body. The cremaster reflex can also be stimulated by rubbing the genitofemoral nerve on the inner thigh and by extreme emotion, such as anxiety.

If the cremaster reflex is strong enough, it can result in a retractile testicle, pulling the testicle out of the scrotum and up into the groin.

Causes of an ascending testicle

A small percentage of retractile testicles can become ascending testicles. This means the once-movable testicle becomes stuck in the "up position." Contributing factors may be:

Short spermatic cord. Each testicle is attached to the end of the spermatic cord, which extends down from the groin and into the scrotum. The cord houses blood vessels, nerves and the tube that carries semen from the testicle to the penis. If growth of the spermatic cord doesn't keep pace with other body growth, the "tight" cord may pull the testicle up.

A problem with the normal path of a descending testicle. The testicles develop in the abdomen during pregnancy, then drop down into the scrotum. Sometimes part of the fetal structure fails to detach from the abdomen, resulting in an upward pull on the testicle.

Scar tissue from hernia surgery. An inguinal hernia is caused by a small gap in the abdominal lining through which a portion of the intestines can protrude into the groin. Scar tissue following surgery to repair the hernia may limit the growth or elasticity of the spermatic cord.

Retractile testicles are not associated with any ill effects, aside from a greater risk of the testicle becoming an ascending testicle.

Your son's pediatrician can usually diagnose a retractile testicle. However, if he or she believes your son needs treatment, you may then be referred to a doctor who specializes in urinary disorders and problems with male genitals in children (pediatric urologist).

Here's some information to help you get ready for the appointment, and what to expect from your child's doctor.

What you can do

Write down any symptoms your child is experiencing, including any that may seem unrelated to the reason for which you scheduled the appointment.

Write down questions to ask your doctor.

Some basic questions to ask your child's doctor include:

How does a retractile testicle occur?

Does my son need any tests?

Will my son outgrow this condition?

What treatments are available, and which do you recommend?

What types of side effects could there be from treatment?

Are there any alternatives to the primary approach that you're suggesting?

After surgery, how often does my son need to have follow-up doctor's appointments?

Will my son have any activity restrictions?

Are there any brochures or other printed material that I can take home with me? What websites do you recommend visiting?

What to expect from your doctor

Your doctor is likely to ask you a number of questions:

Does your son ever complain of pain in his groin?

Has your son ever been treated for a hernia?

Has your son experienced any trauma to his genitals?

If your son has a testicle not located in the scrotum, his doctor will determine its location in the groin. Once it's located, the doctor will attempt to guide it gently into its proper position in the scrotum.

Your son may be lying down, sitting or standing during this examination. If your son is a toddler, the doctor may have him sit with the soles of his feet touching and knees to the side. Older boys may be asked to squat. These positions make it easier to find and manipulate the testicle. In addition, it's important that this exam is done in a warm location and that the doctor has warm hands, because cold can stimulate the cremaster reflex.

If the testicle is a retractile testicle, it will move relatively easily and painlessly. The retractile testicle won't immediately move up again. Your son's doctor can then stimulate the reflex of the cremaster muscle by gently rubbing the upper inside of the thigh. This stimulation will usually cause the retractile testicle to move up again.

If the testicle in the groin moves only part way into the scrotum, if the movement causes pain or discomfort, or if the testicle immediately retreats to its original location, it's most likely not a retractile testicle. The testicle would be considered undescended or ascending (if the testicle had been in the scrotum at one time).

X-rays, ultrasound and MRI are not generally helpful in determining whether testes are retractile or not.

A retractile testicle is likely to descend on its own before or during puberty. If your son has a retractile testicle, your son's doctor will monitor any changes in the testicle's position in annual evaluations to determine if it stays in the scrotum, remains retractile or becomes an ascending testicle.

If the testicle has ascended — no longer movable by hand — or if it's still retractile by age 14, your son's doctor may recommend treatment to move the testicle permanently into the scrotum. Treatments include:

Surgery. In a surgical procedure (orchiopexy), the surgeon guides the testicle to its proper position in the scrotum and stitches it into place. Follow-up exams are usually recommended. Ask your child's doctor how often he needs to be seen.

Hormone therapy. Because descent of the testicle is partially regulated by hormones, descent can sometimes be induced with hormone therapy using human chorionic gonadotropin (HCG) injections.

Adolescent boys and men who have had treatments to correct an ascending or retractile testicle should regularly monitor the position of the testicle to ensure it doesn't ascend at a later time.

You can help your son by being aware of the development of his body and talking to him about it.

Check the position of the testicles regularly during diaper changing or at bath time. Keep a record of changes.

Give your son the vocabulary to talk about the scrotum and testicles. Explain that there are usually two testicles in the scrotum.

When he's about to reach puberty — usually around sixth grade — and you're talking about what physical changes to expect, explain how he can check the testicles himself.

If your son has a retractile testicle, he may be sensitive about his appearance. He may have anxieties about looking different from friends or classmates, especially if he has to undress in front of others in gym class. The following strategies may help him cope:

Explain in simple terms what a retractile testicle is.

Remind him that there's nothing wrong with him.

Explain that the position of the testicle is something you, your son and his pediatrician will pay attention to and fix if necessary.

Help him practice a response if he's teased or asked about the condition.

Buy loosefitting boxer shorts and swim trunks that may make the condition less noticeable when changing clothes and playing sports at school.

Be aware of signs of anxiety, such as not participating in sports that he would normally enjoy.

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